whalen



(No Model.)

B. F. WHALEN, G. W. '0ASE & A. O. GARDNER.

RAILWAY BRAKE SHOE.

bra-412,572. Patented Oct. 8, 1889.

M UNITED STATES PATENT OFFICE.

RIoIIARn F. WHALEN, CHARLES w. cAsE, AND ARTHUR 0. GARDNER, or'HANNIBAL, MIssouRI, ASSIGNORS OFTWO-FIFTHS T ERVIN 0. men

AND WILLIAM w. DRIGGS, OF s ME PLACE.

RAILWAY-BRAKE SHOE.

SPECIFICATION forming part of Letters Patent No. 412,572, dated October8, 1889.

Application filed January 7, 1889. $erial No. 297,748. (No model.)

To all whom it may concerm Be'it known that we, RICHARD WHALEN, OnARLnsW. GAsE, and ARTHUR O. GARD- NEE, citizens of the United States,residing at- Hannibal, in the county of Marion and State of Missouri,have invented an Improvement in Railway-Brake Shoes, of which thefollowing is a specification.

The object of our invention is to increase to the wearing properties ofrailway-brake shoes and to prolong the service of the wheels upon whichthey are applied.

Our invention consists of a brake-shoe the wearing-surface of which iscomposed of iron I5 or steel alternating with any alloy of lead andantimony or its equivalent;

The accompanying drawings illustrate our improvement, Figure 1representing a perspective View of our composite-metal brake- :0 shoe,and Fig. 2 a vertical section through the shoe.

The body of the shoe A, which may be of any desired shape, is first castof iron or steel, with a series of cavities or recesses in thewearing-surface extending partially through the body. These cavities orrecesses are most easily formed by what is known as the coring process.They may vary in size and shape, but should be distributed about equallyo distant apart throughout the face of the shoe and should'extendthrough the wearing depth of the shoe. The composition metal B, havingbeen heated until it assumes a molten state, is poured into thesecavities or 3 5 recesses until they are filled.

The composition metal 13 is composed of lead and antimony in varyingparts, according to the degree of hardness necessary to withstand thefrictional heat generated. For

roads of ordinary grades we prefer twenty to forty parts of antimonywith sixty to eighty parts of lead. We do not, however, desire to belimited to these proportions, as for freight-car service less thantwenty parts of antimony can be used with good results, and on roadswith long and steep grades we may desire to use a larger proportion ofan properties of the shoe.

timony, and in extreme cases antimony alone might be necessary. While weprefer an alloy of lead and antimony, we could use with good results anyother metal or metals regarded as poor conductors of heat that wouldproduce the desired degree of hard- It is a well-known fact that thebrakeshoes in common use constructed wholly of iron or steel whenapplied to the wheel produce friction, from which arises a high de greeof heat both in the wheel and shoe. This high degree of heat destroysthe chill of the wheel and causes a rapid disintegration of both wheeland shoe. The alloy or composition metal described above is a poorconductor of heat, and when introduced into the wearing-surface of abrake-shoe in the manner above described obstructs the current of heatpassing through the shoe and to the wheel and does not impair thefrictional The wearing properties of both shoe and wheel are increasedin proportion as the heat caused by frictional contact is decreased, andthe reduction of this heat depends largely upon the frequencywithgwrhich the sections of composition metal appear in thewearing-surface of the shoe.

It has heretofore been proposed to construct a brake shoe of cast-ironwith a lead filling, which is to act asa dry lubricant on the face ofthe wheel and shoe. A shoe constructed with this filling does notaccomplish our purpose, as a filling of pure lead or an alloy as soft aslead, under the heat generated by constant frictional application to thewheel, becomes too soft and will not remain in the grooves, but runs outand disappears. Anti- 8 5 mony being a much harder metal than lead, aswell as a poor conductor of heat, produces when combined with lead analloy sufliciently hard to withstand the heat, and will remain in thebody until the shoe is worn out.

It has also been proposed to construct a shoe of a cast-metal bodyhaving rods of a softer metal than the body extending entirely throughit and cast into it; This form of construction does not answer ourpurpose, steel body filled with lead and antimony, subas a metal softerthan refined iron cannot be stantially as described. used for the rodsin combination with a cast RICHARD F. WHALEN. iron or steel body.CHARLES W. CASE.

5 hat we claim as new, and desire to secure ARTHUR O. GARDNER.

by Letters Patent, is Witnesses:

As an improved article of manufacture, a EUGENE D. WARREN, railway-brakeshoe composed of an iron or ARTHUR H. LUND.

